Remove pending probes on update_fail

Previously we had a memory leak where probes would not be removed from
outbound_payments on htlc fail

Author: valentinewallace

lightning/src/ln/outbound_payment.rs

@@ -1062,17 +1062,19 @@ impl OutboundPayments {
 				});
 			}
 
-			if !payment_is_probe && (!is_retryable_now || !payment_retryable || retry.is_none()) {
+			if payment_is_probe || !is_retryable_now || !payment_retryable || retry.is_none() {
 				let _ = payment.get_mut().mark_abandoned(); // we'll only Err if it's a legacy payment
 				is_retryable_now = false;
 			}
 			if payment.get().remaining_parts() == 0 {
 				all_paths_failed = true;
 				if payment.get().abandoned() {
-					full_failure_ev = Some(events::Event::PaymentFailed {
-						payment_id: *payment_id,
-						payment_hash: payment.get().payment_hash().expect("PendingOutboundPayments::RetriesExceeded always has a payment hash set"),
-					});
+					if !payment_is_probe {
+						full_failure_ev = Some(events::Event::PaymentFailed {
+							payment_id: *payment_id,
+							payment_hash: payment.get().payment_hash().expect("PendingOutboundPayments::RetriesExceeded always has a payment hash set"),
+						});
+					}
 					payment.remove();
 				}
 			}

lightning/src/ln/payment_tests.rs

@@ -941,6 +941,7 @@ fn successful_probe_yields_event() {
 		},
 		_ => panic!(),
 	};
+	assert!(!nodes[0].node.has_pending_payments());
 }
 
 #[test]
@@ -986,6 +987,7 @@ fn failed_probe_yields_event() {
 		},
 		_ => panic!(),
 	};
+	assert!(!nodes[0].node.has_pending_payments());
 }
 
 #[test]
@@ -1040,6 +1042,7 @@ fn onchain_failed_probe_yields_event() {
 		}
 	}
 	assert!(found_probe_failed);
+	assert!(!nodes[0].node.has_pending_payments());
 }
 
 #[test]